The present invention relates to a tape recorder such as a telephone answering and recording device and, particularly, to a method of recording a time instance at which a message is transmitted through a telephone line and indicating the latter when the message is reproduced later.
In such a tape recorder which responds to a telephone call signal to transmit prerecorded announcement and record a message transmitted by a caller when a subscriber is absent, it is convenient for the subscriber to know the time instance at which the message is received. In order to realize this, it has been proposed to record the time instance by using an audible watch whose time signal is recorded simultaneously on the magnetic tape with the message. It is possible to use a portion of a broadcasting program instead of the audible watch. Another method proposed is to record, together with the message, a time signal provided by an automatic dialing system.
The method of using the audible watch or the automatic dialing system requires a complicated hardware and thus the cost therefor is very high, causing the realization thereof to be difficult. In the method of using the broadcasting program the subscriber must be highly trained, otherwise this method becomes unusable. Furthermore, in this method it is very difficult to determine the exact time instance.